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  • 静电和静电消减

    A person standing on a welcome mat that says 'Wipe Your Paws!'}

    You’re a thoughtful visitor, so you wipe your feet on the welcome mat before you reach out to touch the brass knocker on the door. Ouch! A spark suddenly jumps between your hand and the metal , and you feel an electric shock.
    ::你是一个深思熟虑的访客,所以你先在欢迎席上擦擦脚,然后再伸出手来触摸门上的黄铜敲门机。 哎哟!一个火花突然从你的手和金属之间跳出来,你感到电击。

    Q: Why do you think an electric shock occurs when you touch the brass knocker after wiping your feet on the welcome mat?
    ::问:你为什么认为当你在欢迎席上擦脚后碰到黄铜敲门门时会发生电击?

    A: A static electric shock occurs when static electricity is suddenly discharged.
    ::A:静电突然放电时发生静电冲击。

    What Is Static Electricity?
    ::什么是静电?

    Static electricity is a buildup of electric charges on objects. Charges build up when negative electrons are transferred from one object to another. The object that gives up electrons becomes positively charged, and the object that accepts the electrons becomes negatively charged. This can happen in several ways.
    ::静电是静电对物体电费的积累。 当负电子从一个物体转移到另一个物体时,电费会累积起来。 放弃电子的物体会受到正电, 接受电子的物体会受到负电费。 这可以通过几种方式发生。

    One way electric charges can build up is through between materials that differ in their ability to give up or accept electrons. When you wipe your rubber-soled shoes on the wool mat, for example, electrons rub off the mat onto your shoes. As a result of this transfer of electrons, positive charges build up on the mat and negative charges build up on you.
    ::电费可以通过电费积累的方式之一,是介于它们放弃或接受电子能力不同的材料之间。 当你在羊毛垫上擦擦你的橡胶胶片鞋时,比如说,电子从垫子上擦到鞋上。由于电子转移,正电费在垫子上积聚,负电费在你身上积聚。

    Once an object becomes electrically charged, it is likely to remain charged until it touches another object or at least comes very close to another object. That’s because electric charges cannot travel easily through air, especially if the air is dry.
    ::一旦一个物体充电,它可能会继续充电,直到它碰到另一个物体,或至少非常接近另一个物体。 这是因为电费不能轻易地通过空气,特别是如果空气干燥的话。

    Q: You’re more likely to get a shock in the winter when the air is very dry. Can you explain why?
    ::问题:当空气非常干燥时,你更可能在冬天受到冲击。你能解释为什么吗?

    A: When the air is very dry, electric charges are more likely to build up objects because they cannot travel easily through the dry air. This makes a shock more likely when you touch another object.
    ::A:当空气非常干燥时,电荷更有可能堆积物体,因为它们无法轻松地穿透干燥空气。这样一来,触碰另一个物体就更有可能受到冲击。

    Static Discharge
    ::静静解

    What happens when you have become negatively charged and your hand approaches the metal doorknocker? Your negatively charged hand repels electrons in the metal, so the electrons move to the other side of the knocker. This makes the side of the knocker closest to your hand positively charged. As your negatively charged hand gets very close to the positively charged side of the metal, the air between your hand and the knocker also becomes electrically charged. This allows electrons to suddenly flow from your hand to the knocker. The sudden flow of electrons is static discharge . The discharge of electrons is the spark you see and the shock you feel. 
    ::当您的手受到负电荷,而您的手接近金属门把手时会发生什么情况? 您的负电手反射器在金属中电子, 因此电子会移动到敲门器的另一侧。 这使得敲门器的侧最接近您的手, 积极电压。 当您的负电动手非常接近金属的正电压侧时, 你的手和敲门器之间的空气也会被电压。 这让电子突然从你的手流向敲门器。 电子的突然流动是静态的释放。 电子的释放是您看到的火花, 也是你感受到的冲击。

    How Lightning Occurs
    ::闪电暗点如何

    Another example of static discharge, but on a much larger scale, is lightning. You can see how it occurs in the following diagram ( Figure ).
    ::静态排放的另一个例子,但规模大得多的是闪电。您可以从下图(图 )中看到它是如何发生的。

    Illustration explaining lightning formation with negative and positive charges in clouds.

    During a rainstorm, clouds develop regions of positive and negative charge due to the movement of air molecules, water drops, and ice particles. The negative charges are concentrated at the of the clouds, and the positive charges are concentrated at the top. The negative charges repel electrons on the ground beneath them, so the ground below the clouds becomes positively charged. At first, the atmosphere prevents electrons from flowing away from areas of negative charge and toward areas of positive charge. As more charges build up, however, the air between the oppositely charged areas also becomes charged. When this happens, static electricity is discharged as bolts of lightning.
    ::在暴风雨期间,云层会发展出由于空气分子、水滴和冰粒的移动而产生正负电荷的区域。负电荷集中在云层,正电荷集中在顶部。负电荷将地下电子排出,因此云层下的地面会发生积极电荷。首先,大气层会防止电子从负电荷区向正电荷区流动。然而,随着更多的电量增加,相反电荷区之间的空气也会被充电。一旦发生这种情况,静电就会作为闪电的电栓排放。

     

     

    To learn more about lightning, launch the Lightning Rod simulation below. A djust the Charge Separation slider to high, the Cloud Separation slider to low, and be sure to turn the Lightning Rod on (to protect the people in the building). Then, press play and see what happens:
    ::要了解更多闪电知识, 请在下面启动闪电模拟。 将电荷分离滑板调整到高, 云层分离滑板调整到低, 并且一定要打开闪电滑板( 以保护大楼里的人)。 然后按下播放, 看看会发生什么 :

     

     

    Summary
    ::摘要

    • Static electricity is a buildup of electric charges on objects. It occurs when electrons are transferred from one object to another.
      ::静态电力是对物体的电费累积,当电子从一个物体转移到另一个物体时即发生。
    • A sudden flow of electrons from one charged object to another is called static discharge.
      ::电子从一个充电物体突然流向另一个物体,称为静态排放。
    • Examples of static discharge include lightning and the shock you sometimes feel when you touch another object.
      ::静态释放的例子包括闪电和当你触碰另一个物体时你有时感受到的冲击。

    Review
    ::回顾

    1. What is static electricity?
      ::什么是静电?
    2. How does static discharge occur?
      ::静态排放是如何发生的?
    3. Explain why a bolt of lightning is like the spark you might see when you touch a metal object and get a shock.
      ::解释一下为什么闪电闪电就像 触碰金属物体时你可能看到的火花 并受到冲击